<mat-tab-group>
  <mat-tab>
    <ng-template mat-tab-label>
      BUY
    </ng-template>
    <div class="spacer">
    <app-buy-form></app-buy-form>
  </div>
  </mat-tab>
  <mat-tab>
    <ng-template mat-tab-label>
      SELL
    </ng-template>
    <div class="spacer">
        <app-sell-form></app-sell-form>
  </div>
  </mat-tab>
</mat-tab-group>